EP3421139A1 - Method and device for spraying a liquid to a panel-shaped workpiece - Google Patents

Abstract

Method for processing a plate-shaped workpiece (1), comprising at least the following steps:
a) providing a spray container (2) with a liquid (3),
b) pumping a gas into the spray medium container (2) to generate an overpressure in a liquid space (4) of the spray medium container (2) so that the liquid (3) is sprayed from a nozzle (5) connected to the spray medium container (2),
c) stopping the pumping of the gas in the spray container (2), so that the spraying of the liquid is stopped,
wherein during step b) and step c) at least part of the gas escapes from a gas opening (6) of the spray container (2) from the spray container (2), so that the overpressure in the liquid chamber (4) after the completion of the spraying of the liquid ( 3) in step c) decreases. In addition, a device for spraying a liquid and a use of a corresponding device for the continuous processing of a plate-shaped workpiece is proposed.

Description

The invention relates to a method for processing a plate-shaped workpiece, a device for spraying a liquid and a use of such a device for the continuous processing of a plate-shaped workpiece.

It is known that plate-shaped workpieces, such as furniture panels made of wood or a wood material, edge side or on its narrow side with a so-called edge band are coated. This is done in modern furniture manufacturing companies usually by means of at least one furniture plate in the processing machine. Such machines are also referred to as a continuous machine and / or edge banding machine. Within this machine, the furniture panel is moved, for example by means of at least one conveyor belt (continuously) progressively from one processing station to the next. Thus, the furniture panel passes through the machine.

The edge band also serves in particular to improve the appearance of the furniture panel and hereby complements the regularly existing on the upper and / or lower broad side of the furniture panel decorative layer. In addition, the wooden core of the furniture panel is protected by the edge band and decorative layers. The edge band is usually made of polishable plastic, such. As acrylic or the like and can be tackified at least on one side by a thermal treatment, wherein the thermal treatment, for example, by means of at least one laser beam or by means of plasma jets. Alternatively or cumulatively, an adhesive can be applied to the edge band and / or the narrow side of the furniture panel before mounting.

When attaching the edge band or when coating the narrow side of the furniture panel with the edge band, however, it should be prevented that the decor layer already present on the underside and / or top broad side of the furniture panel is damaged and / or permanently contaminated. In this context, particular care must be taken to ensure that adhesive residues, material emerging from the adhesive joint between edge band and furniture panel (adhesive and / or liquefied or molten plastic) and / or (milling) chips do not permanently adhere to the decor layer (s) ) can adhere.

For this purpose, a release agent and / or an antistatic agent and / or another fluid applied at least on portions of the underside and / or top-side broad side of the furniture panel. In this case, the release agent is applied at least in an edge region of the broad side which is assigned to the edge band to be attached, in order to prevent adhesion of adhesive in this marginal side region of the broad side. Here, particularly good results could be achieved with release agents that adhere relatively strongly or firmly to the surface of the furniture panel. Furthermore, the release agent and / or the antistatic agent can also be applied to machining tools, such as milling, peeling blades and / or buffing wheels, of the machine.

For applying the release agent and / or the antistatic agent and / or other fluid spray devices may be provided which cooperate with Sprühmittelbehälter in which the fluid is stored. The Sprühmittelbehälter can be connected to a pressure generator, by means of which in the Sprühmittelbehälter an overpressure can be generated, so Fluid is sprayed through a connected to the spray container nozzle on the furniture plate or the processing tools. A disadvantage of these spraying devices, however, is that the fluid can not be metered precisely because the overpressure in the spraying agent container degrades only slowly after the pressure generator has been switched off. Furthermore, the overpressure in the Sprühmittelbehälter after switching off the pressure generator often does not build off completely, so that the pressure must be reduced manually before changing the Sprühmittelbehälters by carefully opening a lid of the Sprühmittelbehälters. In addition, such systems can be complex and costly and possibly require additional approvals.

The object of the invention is therefore to solve the problems described at least partially and in particular to provide a method for processing a plate-shaped workpiece, in which the application of a liquid is particularly precisely metered. In addition, a device for spraying a liquid is to be specified, with which the liquid is particularly precisely metered. Furthermore, a use of a corresponding device is to be specified, by which a liquid is particularly precisely metered.

To solve these objects, a method, a device and a use according to the features of the independent claims contribute. Further advantageous embodiments of the invention are specified in the dependent claims. It should be noted that the features listed individually in the dependent claims can be combined with each other in any technologically meaningful manner and define further embodiments of the invention. In addition, those specified in the claims Features in the description specified and explained in more detail, wherein further preferred embodiments of the invention are shown.

1. a) Bereitstellen eines Sprühmittelbehälters mit einer Flüssigkeit,
2. b) Pumpen eines Gases in den Sprühmittelbehälter zur Erzeugung eines Überdrucks in einem Flüssigkeitsraum des Sprühmittelbehälters, sodass die Flüssigkeit aus einer mit dem Sprühmittelbehälter verbundenen Düse gesprüht wird,
3. c) Beenden des Pumpens des Gases in den Sprühmittelbehälter, wenn das Sprühen der Flüssigkeit gestoppt werden soll,

wobei zumindest während Schritt b) oder Schritt c) zumindest ein Teil des Gases aus einer Gasöffnung des Sprühmittelbehälters aus dem Sprühmittelbehälter entweicht, sodass der Überdruck in dem Flüssigkeitsraum nach dem Beenden des Sprühens der Flüssigkeit in Schritt c) sinkt.For this purpose, a method for processing a plate-shaped workpiece has at least the following steps:

1. a) providing a spray container with a liquid,
2. b) pumping a gas into the spray medium container to create a positive pressure in a liquid space of the spray medium tank so that the liquid is sprayed from a nozzle connected to the spray medium tank,
3. c) stopping the pumping of the gas into the spray container, if the spraying of the liquid is to be stopped,

wherein at least during step b) or step c) at least a part of the gas escapes from a gas opening of the Sprühmittelbehälters from the Sprühmittelbehälter so that the pressure in the liquid space after the completion of the spraying of the liquid in step c) decreases.

The proposed method is used in particular for the continuous processing of a plate-shaped workpiece. The plate-shaped workpiece may, for example, be a wooden plate, furniture plate, table top, worktop or the like.

In step a), a spray container is provided with a liquid in the region of the plate-shaped workpiece or a processing machine, such as an edge banding machine, for the plate-shaped workpiece. The liquid may be a release agent and / or an antistatic agent and / or a polishing agent and / or a cleaning fluid. The spray container is in particular a (plastic) container or (plastic) canister. Of the Sprühmittelbehälter has a liquid space for the liquid, which in particular has a volume of 5 liters to 25 liters.

In step b), a gas is pumped into the spray container to create an overpressure in the liquid space. For this purpose, a pressure generator, for example in the manner of an (electric) pump, be connected via a pressure line with the Sprühmittelbehälter. The gas is in particular air from an environment of the spray container. Due to the overpressure, the liquid is supplied from the liquid space via a liquid line to a nozzle, which sprays the liquid (in the manner of a spray). The spraying of the liquid can take place, for example, on the plate-shaped workpiece and / or on a machining tool for the plate-shaped workpiece.

In step c), the pumping of the gas into the spray container is stopped, so that the spraying of the liquid is stopped. For this purpose, a sensor or the like may be provided, with which it can be detected when a plate-shaped workpiece is located in front of the nozzle or when there is a gap between successive plate-shaped workpieces to be processed. Preferably, the spraying is (always) stopped when there is no plate-shaped workpiece in front of the nozzle.

The process steps a) to c) can therefore repeat very often and quickly.

During step b) and / or step c) escapes at least a portion of the gas from a gas opening of the Sprühmittelbehälters from the Sprühmittelbehälter. The gas opening is in particular an opening in the spray container, through which the liquid space of the spray medium container is connected to an environment. The gas opening may be permanently open and / or in particular has a diameter of up to 10 mm [millimeters]. The gas opening may be temporarily open, z. B. by a closure means or valve operated therein (open / closed) is. The gas opening can optionally be opened depending on the pressure, z. B. (automatically) when reaching or exceeding a limit pressure in Sprühmittelbehälter.

Furthermore, the gas opening is arranged in particular on a ceiling, in particular in the region of a closure element, of the liquid space. Furthermore, preferably no liquid emerges from the gas opening during the spraying of the liquid. As a result, the overpressure in the liquid space drops immediately after the end of the spraying of the liquid in step c), so that the spraying off of the liquid is stopped immediately when the pressure generator is switched off. As a result, the liquid can be applied and dosed particularly accurately.

In addition, it is advantageous if the overpressure in the liquid space after the end of the spraying of the liquid in step c) drops to atmospheric pressure. The atmospheric pressure is in particular a hydrostatic pressure of the air in the vicinity of the spray container. The atmospheric pressure is in particular about 1 bar.

Furthermore, it is advantageous if, by pumping the gas into the spray container in step b), an overpressure in the liquid space of 0.05 bar to 0.3 bar above an atmospheric pressure is generated. The overpressure in the liquid space is preferably 0.1 bar to 0.2 bar, very particularly preferably about 0.15 bar.

In addition, it can be provided that the gas is filtered during the escape from the gas opening. For this purpose, in particular a filter is arranged in the gas opening. The filter in particular leakage of liquid, aerosols, vapors and / or odors from the Sprühmittelbehälter be prevented.

It is also advantageous if a sound generated when the gas escapes from the gas opening is damped. For this purpose, a silencer may be arranged in the region of the gas opening.

• einen Sprühmittelbehälter mit einem Flüssigkeitsraum für eine Flüssigkeit,
• einen Druckerzeuger zum Pumpen eines Gases in den Sprühmittelbehälter zur Erzeugung eines Überdrucks in dem Flüssigkeitsraum,
• eine Düse zum Versprühen der Flüssigkeit, wobei die Düse über eine Flüssigkeitsleitung mit dem Flüssigkeitsraum verbunden ist, und
• eine Gasöffnung, durch die das Gas aus dem Flüssigkeitsraum entweichen kann.

Furthermore, a device for spraying a liquid is disclosed which has at least the following components:

• a spray container having a liquid space for a liquid,
• a pressure generator for pumping a gas into the spray container for generating an overpressure in the liquid space,
• a nozzle for spraying the liquid, wherein the nozzle is connected via a fluid line with the liquid space, and
• a gas opening through which the gas can escape from the liquid space.

In particular, the device is set up so that it serves to carry out the method proposed here. Regardless of this, reference is made to the description of the method according to the invention for further details.

By the gas opening, an outlet of gas can be achieved in the environment. The gas opening may be formed (in the manner of a diaphragm) such that the pressure drop occurs in a coordinated manner and / or in dependence the pressure provided in the Sprühmittelbehälter is desired.

The gas opening may have a filter. The filter is in particular a gas filter.

The gas opening may have a muffler.

The gas opening may have a (pressure-dependent) valve.

Moreover, it is advantageous if the gas opening is formed in a lid of the Sprühmittelbehälters. The lid is in particular a screw cap of the spray container.

In addition, a use of a device for continuous processing of a plate-shaped workpiece is proposed. In the continuous processing of the plate-shaped workpiece, the plate-shaped workpiece or a plurality of plate-shaped workpieces is guided past the device. Alternatively, the device can also be guided past the plate-shaped workpiece or the plurality of plate-shaped workpieces.

Fig. 1:

eine Vorrichtung zum Sprühen einer Flüssigkeit auf ein plattenförmiges Werkstück, und

Fig. 2:

eine Ausführungsvariante eines Anschlussadapters für einen Sprühmittelbehälter.

The invention and the technical environment will be explained in more detail with reference to the accompanying figures. It should be noted that the figures show particularly preferred embodiments of the invention, but this is not limited thereto. They show by way of example and schematically:

Fig. 1:

a device for spraying a liquid onto a plate-shaped workpiece, and

Fig. 2:

an embodiment of a connection adapter for a Sprühmittelbehälter.

The Fig. 1 shows a device 12 for spraying a liquid 3 on a plate-shaped workpiece 1. The device 12 comprises a Sprühmittelbehälter 2 with a liquid space 4, which is bounded by a bottom 13, a ceiling 16 and side walls 17. In the liquid space 4 is the liquid 3. In the ceiling 16, a lid 11 of the Sprühmittelbehälters 2 is arranged. Through the lid 11, a pressure line 14 is guided by a pressure generator 7 in the liquid space 4. By means of the pressure generator 7 is a gas or air pumped from an environment 15 in the liquid space 4, so that in the liquid space 4, an overpressure can be generated. Due to the overpressure in the liquid space 4, the liquid 3 via a liquid line 8, which leads from the bottom 13 of the liquid space 4 through the lid 11 to a nozzle 5, to the nozzle 5 feasible, so that the liquid 3 on the plate-shaped workpiece 1 can be sprayed is. The cover 11 also has a permanently open gas opening 6, through which at least part of the gas or part of the air can escape from the liquid space 4. As a result, the overpressure in the liquid space 4 drops immediately after the deactivation of the pressure generator 7, until a pressure in the liquid space 4 (substantially) corresponds to an atmospheric pressure in the region of the environment 15. In addition, a filter 9 and a muffler 10 are arranged in the gas opening 6.

Fig. 2 illustrates a connection adapter 18, as it can be used together with a cover 11 of a Sprühmittelbehälters 2 for the realization of a device 12.

The connection adapter 11 may be a z. B. metallic body 19 include an upper part 20 and a lower part 21 which are delimited from each other by an outer circumferential shoulder 22. The lower part 21 may be shaped in the manner of a cone, for example, to facilitate the insertion of the connection adapter 18 in the Sprühmittelbehälter 11. The shoulder 22 can act as a support / stop or stop when the connection adapter 18 is inserted into the spray container 11. A lid 11, which is (also) used to seal the Sprühmittelbehälter 11, has a central opening, and thus can be placed over the upper part 20 and placed on the side opposite the Sprühmittelbehälter 11 side with the shoulder 22 in contact. The lid 11 can serve for fixing or tensioning the connection adapter 18 with the spray container 11.

The connection adapter 18 may have three through holes. The connection adapter 18 may include a first connection line 23 for the pressure line 14 and a second connection line 24 for the liquid line 8. It is possible that these connection lines 23, 24 are provided with threads 25 which ensure a fluid-tight and stable connection. Furthermore, a gas opening 6 is provided into which a valve is introduced. The valve 26 can open differential-pressure-controlled (self-acting) when a certain boundary pressure in the Sprühmittelbehälter 2 occurs and possibly close again (self-acting) when a certain limit pressure in the Sprühmittelbehälter 2 is exceeded.

By the present invention, a liquid is particularly precisely metered.

LIST OF REFERENCE NUMBERS

1

plate-shaped workpiece

2

spraying agent

3

liquid

4

liquid space

5

jet

6

gas opening

7

pressure generator

8th

liquid line

9

filter

10

silencer

11

cover

12

contraption

13

ground

14

pressure line

15

Surroundings

16

blanket

17

Side wall

18

connection adapter

19

body

20

top

21

lower part

22

paragraph

23

first connection line

24

second connecting cable

25

thread

26

Valve

Claims (11)

Method for processing a plate-shaped workpiece (1), comprising at least the following steps: a) providing a spray container (2) with a liquid (3), b) pumping a gas into the spray medium container (2) to generate an overpressure in a liquid space (4) of the spray medium container (2) so that the liquid (3) is sprayed from a nozzle (5) connected to the spray medium container (2), c) stopping the pumping of the gas into the spray container (2), if the spraying of the liquid is to be stopped, wherein at least during step b) or step c) at least a part of the gas from a gas opening (6) of the Sprühmittelbehälters (2) escapes from the Sprühmittelbehälter (2), so that the overpressure in the liquid space (4) after the completion of the spraying of the liquid (3) in step c) decreases. Method according to claim 1, wherein the overpressure in the liquid space (4) after the completion of the spraying of the liquid (3) in step c) decreases to atmospheric pressure. Method according to one of the preceding claims, wherein by the pumping of the gas in the Sprühmittelbehälter (2) in step b) an overpressure in the liquid space (4) of 0.05 bar to 0.3 bar above an atmospheric pressure is generated. Method according to one of the preceding claims, wherein the gas is filtered during the escape from the gas opening (6). Method according to one of the preceding claims, wherein a sound generated when the gas escapes from the gas opening (6) is damped. Apparatus (12) for spraying a liquid (3), comprising: a spray container (2) having a liquid space (4) for a liquid (3), - A pressure generator (7) for pumping a gas into the Sprühmittelbehälter (2) for generating an overpressure in the liquid space (4), - A nozzle (5) for spraying the liquid (3), wherein the nozzle (5) via a liquid line (8) with the liquid space (4) is connected, and - A gas opening (6) through which the gas from the liquid space (4) can escape. Device (12) according to claim 6, wherein the gas opening (6) has a filter (9). Device according to claim 6 or 7, wherein the gas opening (6) has a silencer (10). Device according to one of the claims 6 to 8, wherein the gas opening (6) has a valve (26) Device (12) according to one of the claims 6 to 9, wherein the gas opening (6) in a lid (11) of the Sprühmittelbehälters (2) is formed. Use of a device (12) according to one of the claims 6 to 10 for the continuous processing of a plate-shaped workpiece (1).

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